Complete HarpWeek Explanation:Shortly after his nomination for vice president in June 1900, Theodore Roosevelt wrote Mark Hanna, “I am as strong as a bull moose, and you can use me to the limit.” The National Republican Party chairman did so, sending the candidate on an energetic campaign tour across the nation. When Roosevelt ran for president in 1912, his previous remark was remembered by his California supporters who called themselves “Bull Moosers.” The animal was quickly adopted by cartoonists as a symbol for the new Progressive Party, which in August nominated Roosevelt for president. Here, the Progressive Bull Moose bears Roosevelt’s characteristic toothy grin and eyeglasses, while the Democratic Donkey and wounded Republican Elephant observe from behind the political fence.

The water barrel refers to George W. Perkins, a wealthy businessman who served as chairman of the Progressive Party and contributed generously to Roosevelt’s campaign. As a partner for J. P. Morgan and Company (1901-1910), Perkins had arranged the merger that established the International Harvester Company and served on its board of directors. Critics argued that creation of the company violated antitrust laws, and Roosevelt’s association with him was controversial even within the Progressive Party.